Possible Clues:

• Sporting side I rave about from a bygone era
• I get angry about working during this period
• Period piece central in Thirsk on decline
• When metal-casting started
• Period in the history of man — a region (anag)
• Club linked to a good English period of old
• Period in human history
• Time when people got super into metal?
• When bronze was replaced, historically
• Historic period of strength ahead of time